The ribs of a 240 million year old fossil hold clues to how the first turtle shell evolved and its skull shape seems closer to that of lizards and snakes . How the turtle got its shell justine fontes ron fontes keiko motoyama on amazoncom free shipping on qualifying offers delightful retellings of turtle tales . The turtle shell isnt like any other protective element of any living animal its not an exoskeleton like some invertebrates have nor is it made of . A newly discovered fossil helped scientists solve the kipling esque saga of the turtle shells origin